Alpha sea trials

The nation’s newest and most advanced nuclear-powered attack submarine, USS Colorado (SSN-788), returned to the General Dynamics Electric Boat shipyard Monday, August 21, following the successful completion of its first voyage in open seas, called alpha sea trials. Colorado is the 15th ship of the Virginia Class, the most capable class of attack submarines ever built. Electric Boat is a wholly owned subsidiary of General Dynamics (GD).

Submarine Colorado completes first voyage
Submarine Colorado completes first voyage

Colorado’s alpha sea trials included a range of submarine and propulsion-plant operations, submerging for the first time, and high-speed runs on and below the surface to demonstrate that the ship’s propulsion plant is fully mission-capable.

The sea trials were directed by U.S. Navy Admiral James F. Caldwell Jr., director – Naval Nuclear Propulsion. Also participating in the sea trials were Captain Jeffrey Heydon, supervisor of shipbuilding in Groton; and Jeffrey S. Geiger, president of Electric Boat. Colorado is commanded by Commander Ken Franklin.

«The crew and shipbuilders worked as one unit to take Colorado to sea and put it through its paces», said Electric Boat President Geiger. «This required an outstanding effort by everyone involved, and demonstrates the commitment of the U.S. Navy and industry team to sustain the success of the Virginia-class submarine program. I appreciate the contributions made by the U.S. Navy personnel, shipbuilders and suppliers who made it happen».

Electric Boat and its construction teammate, Newport News Shipbuilding, already have delivered 14 Virginia-class submarines to the U.S. Navy: USS Virginia (SSN-774), USS Texas (SSN-775), USS Hawaii (SSN-776), USS North Carolina (SSN-777), USS New Hampshire (SSN-778), USS New Mexico (SSN-779), USS Missouri (SSN-780), USS California (SSN-781), USS Mississippi (SSN-782), USS Minnesota (SSN-783), USS North Dakota (SSN-784), USS John Warner (SSN-785), USS Illinois (SSN-786) and Washington (SSN-787). Fourteen more submarines of the class are under contract.

Virginia-class submarines displace 7,835 long tons/7,961 metric tons submerged, with a hull length of 377 feet/114.9 m and a diameter of 34 feet/10.4 m. They are capable of speeds in excess of 25+ knots/29+ mph/46+ km/h and can dive to a depth greater than 800+ feet/244+ m, while carrying Mark 48 advanced capability torpedoes and Tomahawk land-attack missiles.

Ship’s Crest
Ship’s Crest


General Characteristics

Builder General Dynamics Electric Boat Division and Huntington Ingalls Industries Inc. – Newport News Shipbuilding
Date Deployed October 3, 2004
Propulsion One GE PWR S9G* nuclear reactor, two turbines, one shaft; 40,000 hp/30 MW
Length 377 feet/114.9 m
Beam 33 feet/10 m
Hull Diameter 34 feet/10.4 m
Displacement Approximately 7,835 long tons/7,961 metric tons submerged
Speed 25+ knots/29+ mph/46+ km/h
Diving Depth 800+ feet/244+ m
Crew 132: 15 officers; 117 enlisted
Armament: Tomahawk missiles 12 individual VLS (Vertical Launch System) tubes or two 87-in/2.2 m Virginia Payload Tubes (VPTs), each capable of launching 6 Tomahawk cruise missiles
Armament: MK-48 ADCAP (Advanced Capability) Mod 7 heavyweight torpedoes 4 torpedo tubes
Weapons MK-60 CAPTOR (Encapsulated Torpedo) mines, advanced mobile mines and UUVs (Unmanned Underwater Vehicles)

* – Knolls Atomic Power Laboratories


Nuclear Submarine Lineup


Block III

Ship Yard Christening Commissioned Homeport
SSN-784 North Dakota EB 11-2-13 10-25-14 Groton, Connecticut
SSN-785 John Warner NNS 09-06-14 08-01-15 Norfolk, Virginia
SSN-786 Illinois EB 10-10-15 10-29-16 Groton, Connecticut
SSN-787 Washington NNS 03-05-16
SSN-788 Colorado EB 12-03-16
SSN-789 Indiana NNS 04-29-17
SSN-790 South Dakota EB Under Construction
SSN-791 Delaware NNS Under Construction